(1) Field of the Invention
This invention is related to surgical trocar instruments.
(2) Brief Description of the Prior Art
Trocars are sharp-pointed instruments used to puncture a body cavity. Such puncturing is often necessary so that fluids may be drained to or from a body using a cannula which is inserted into the opening. Trocars are also used during endoscopic surgical procedures which basically follow three steps. First, a Veress or other cannula is inserted into the abdominal cavity through the abdominal wall and the cavity is inflated with insufflating gas which is passed through the cannula. After insufflating, a small incision is made in the skin and a trocar spike is thrust into the inflated abdomen through the bore of the trocar tube. Standard trocar "spikes" are shaped like a large metal peg with a sharpened needlenose point at the end. The spike is inserted for purposes of puncturing or cutting of the abdominal wall and piercing the fascia and peritoneum inside the cavity. Thereafter, the trocar spike is removed and an endoscopic surgical instrument is inserted into the abdominal cavity through the trocar tube.
A serious problem associated with conventional and prior art trocar "spikes" is that such devices which are hollow and cylindrically shaped can puncture internal organs and arteries, and also may receive the solids which are cut or punctured within the body cavity to cause same to be contained and housed within the outboard-most end of the trocar spike, resulting in a "coring" effect similar to that experienced when a cylindrical cutting device is inserted through an apple. Such "coring" is undesirable for many obvious reasons, including the fact that a buildup of such solid material interior of the trocar tubular spike can cause trauma, bleeding and damage to organs and arteries, and can further complicate surgical procedures.
The present invention is directed to overcoming the problems associated with prior art trocar spikes.